1. C. O’Ceallaigh:Phil. Mag.,42, 1032 (1951).
2. C. Dahanayake, P. E. Francois, Y. Fujimoto, P. Iredale, C. J. Waddington andM. Yasin:Phil. Mag., (1955) in course of publication.
3. P. H. Fowler andD. H. Prekins:Phil. Mag. (1955), in course of publication.
4. R. R. Daniel andD. Lal:Proc. Ind. Acad. Sci., in course of publication (1955).
5. M. Gell-Mann andA. Pais:Proc. Int. Nucl. Phys. Conf. (Glasgow), July 1954.